applying notch filter on input and output part? - RF Cafe Forums

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ngks

Post subject: applying notch filter on input and output part?

Unread postPosted: Tue Jun 21, 2005 2:13 am

Thanks!! Anybody know that the return loss can be happen is because we design notch filter when we design on input and output impedance parts?

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guest

Post subject: Return Loss

Unread postPosted: Tue Jun 21, 2005 2:30 pm

Energy applied to any physical two-port device made from inductors, capacitors, and transmission lines can only go two places - through the device to the other port, or be reflected back from the device.

Energy which doesn't go through the device must therefore be reflected. Reflected energy reduces the return loss.

The only solution is to dissipate the energy in an attached resistance. This is usually done by paralleling a filter with its complement and terminating the complement with a resistor with eough power handling capability to take care of all the stopband power.

Good Luck!

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Guest

Post subject:

Unread postPosted: Wed Jun 22, 2005 9:00 am

Or, depending on the frequency, use an isolator. Similar to what was said above.

Posted  11/12/2012